1. Field of the Invention
The present invention is directed to a drive system for a harvesting assembly wherein torque sensors signal a controller to disengage and/or brake the rotation of the feed auger.
2. Description of the Prior Art
Agricultural combines are large machines that harvest, thresh, separate and clean an agricultural crop. The resulting clean grain is stored in a grain tank located on the combine. The clean grain can then be transported from the grain tank to a truck, grain cart or other receiving bin by an unloading auger.
A harvesting assembly located at the front of the combine harvests the crop. The harvesting assembly may comprise a harvesting platform or a pickup platform. A harvesting platform has a mower assembly for cutting the standing crop. The cut crop falls onto the platform and is taken up by a feed auger that directs the harvested crop to the feederhouse of a combine. A pickup platform is provided with a pickup assembly for picking up a cut crop lying in a field. The cut crop is directed to a feed auger that directs the harvested crop to the feederhouse. The feed augers on both the harvesting platform and the pickup platform are provided with finger timing shafts. The finger timing shafts are located in the feed augers. Each finger timing shaft is provided with a series of retractable fingers that extend from and retract into the feed auger. The retractable fingers are used to throw the crop into the feederhouse.
The drives for the feed auger are typically provided with a slip clutch to prevent or at least reduce the damage to the auger and the surrounding components caused by an excessive load of harvested crop material. These clutches have been found to be inconsistent and slip at undesirable levels. They do not prevent damage to the retractable fingers.
It is an object of the present invention to provide a system for protecting the feed auger and retractable fingers located therin from excessive loads of harvested crop material.
A harvesting assembly comprises a frame having a transverse feed auger for directing harvested crop material into a feederhouse. The feed auger is rotatably driven relative to the frame by a feed auger drive. The feed auger is also provided with freely rotatable retractable fingers mounted on a finger timing shaft located in the feed auger.
A feed auger torque sensor is mounted to the feed auger and a timing shaft torque sensor is mounted to the finger timing shaft. The feed auger torque sensor provides an actual feed auger torque signal. The timing shaft torque sensor provides an actual timing shaft torque signal. Both actual torque signals are communicated to an electronic controller. The controller is provided with a memory storing a maximum desired feed auger torque signal and a maximum desired finger timing shaft torque signal. The controller compares the actual feed auger torque signal with the maximum desired feed auger torque signal. If the actual feed auger torque signal exceeds the desired feed auger torque signal the feed auger drive is disengaged. The controller also compares the actual timing shaft torque signal with the maximum desired timing shaft torque signal. If the actual timing shaft torque signal exceeds the maximum desired timing shaft torque signal the feed auger drive is declutched and a brake is applied to the feed auger.
The maximum desired torque signals can be selected by an operator through an operator input located in the operator""s cab of the combine.